Updated GoUsers (markdown)
diff --git a/GoUsers.md b/GoUsers.md
index 369a6f9..849d890 100644
--- a/GoUsers.md
+++ b/GoUsers.md
@@ -16,6 +16,7 @@
* [Jam With Chrome](http://www.jamwithchrome.com/technology),
* the [CubeSlam Chrome Experiment](https://code.google.com/p/cubeslam/),
* Google Helpouts,
+ * [Doorman, Global Distributed Client Side Rate Limiting](https://github.com/youtube/doorman)
* and the [pprof command line tool](https://codereview.appspot.com/153750043/).
* [6Wunderkinder](http://www.6wunderkinder.com/) - [video](https://www.youtube.com/watch?v=sVpMc0hwqps)
* [99designs](http://www.99designs.com) - [golang-nuts](https://groups.google.com/d/msg/golang-nuts/eeAmkzaRt-w/rmxBZszJUCcJ)